Sandblasting machine



April 6, 1948. I A, PQRC L 2,438,943

SANDBLAS T ING MACHINE Filed Dec. 23, 1946 FIG 2 INVENTOR.

ALBERT J. PORCELLI ATTORNEY Patented Apr. 6, 1948 UiNaI PAT T OFFIGE N BG MACH NE Albert J. -lw orcelli, New Eork, N. Y.

Applicatiill December 23, 1946, Serial "No. 718,097

,5 :Claims. (Cl. 51--8) (Granted under the act of March 3, 1883, asamended April 30, 1928.; 370 0.. G. ,757)

flhis invention relates toimprovements insande blasting machines inwhich sand or a similar pow dered or granular abrasive is impelledagainst an object to be secured or polished by application of the forceof compressed air.

The Primary object :of this improvement is to provide a novel mechanicalmeans for scouring or polishing anobiect.

A further object is to provide a sandblasting machine of simple anddurable cons-truction wherein the abrasive action will be substantiallyuniform over the entire surface being scoured or polished.

A the ob ect is to provide a blast machine havin a filter ada te o sorba ter a ad d I cm the surf e b i g secu d o p l hed- .A furthe object isto p o ide ndbla t machine in which the sand or other abrasive employedis reclaimed and reused.

Another object is to provide a sandblastin machine that will reducesubstantially the occupational hazard of exposure to atmospherecontaining concentrations of the finely divided particles that areproducts of the operation.

Further objects and advantages of this invention, as well as itsconstruction, arrangement and operation, will be apparent from thefollowing description and claims in connection with the accompanyingdrawing, in which Fig. 1 is a plan view of a sandblasting machine partlybroken away, showing a preferred embodiment of this invention; and

Fig. 2 is a sectional elevation thereof taken on the line 2-2 of Fig. 1and showing an object suspended in the tank of the machine.

Similar numerals refer to similar parts throughout the several views.

A cylindrical tank or cannister I! mounted on legs I3 is provided withmeans to suspend an object to be secured or polished, such as aplurality of angle irons l5 secured to the inner wall of said tank. Aconduit I! provided with a pressure valve I9 is supported by braces 2|on the outer wall of said tank and is led into said tank through a, port23 adjacent the floor 25 thereof. Convolutions of the conduit,preferably in the pattern of a decreasing spiral, cover a substantialportion of the floor of said tank, and a plurality of perforations 21 inthe convoluted portion of said conduit are adapted to direct a stream ofair vertically upward. v

The sandblasting machine is provided with a cover 29 having an annularresilient gasket 3|, which seals said cover hermetically to the upperperiphery of the tank ll, said engagement being retained by a pluralityof clamps or looks 33. An annular inner flange 35 on the lower peripheryof the rim of the cover facilitates seating said cover on the tank andthe resilient ring 3'! mounted on .2 the crest of said flange aids inlimiting displacemen of the-chi ect bein secure portion of the cover i=9is provided with a filter that permits egress of air from the tank whileremoving :foreign substances from such :air. The preterred embodiment"of such filter cornprises successive laminationsof screen 39, mattedfibers :41, porous carbon 43, matted fibers 45 and screen 4'! packed inhorizontal layers within the rim of said cover to form the body thereof.

cover 129 is further provided with :a suitable handle 49 to facilitateplacement and removal.

When a quantity of sand or similar powdered :or granular abrasive 51 isplaced on the floor of the tank, compressed air admitted to the chamheror the tank by opening the valve iii discharges through the perirations21 in the convoluted portion of the conduit and impels particles of saidsand against the object 53, thereby efiecting scouring or polishingaction upon such object. The sand is repelled by impact against suchobject or against the laminated filter and falls toward the floor of thetank, while the air is released through said filter.

It is apparent that solid matter abraded from said object is eithercommingled with the sand, thereby becoming a supplementary abrasive, oradheres to the filter, and that gaseous matter is neutralized by thechemical action of the filter.

-It is further apparent that the repelled sand and solid abraded matteris again accelerated upward against the object and that the cycle isrepeated continually as long as pressure 01 air is maintained. Theplurality of perforations in the convoluted portion of the conduitprovides an upward force that is substantially uniform over the entirecircumference of the tank. When the valve is closed, the sand andabraded solid matto:- rest on-the floor of the tank and the operationcan be repeated upon another object Without replenishing the abrasive,since there is substantial reclamation of the sand used.

Various modifications and changes can be made in the above devicewithout departing from the scope of the invention.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

I claim:

1. A sandblasting machine comprising a tank adapted to contain aquantity of sand, a, conduit adapted to conduct compressed air to theinterior of said tank, the portion of the conduit within said tank beingconvoluted over the floor of said tank and having a plurality ofperforations adapted to facilitate upward flow of air, means adapted tocontain a quantity of sand, a conduit adapted to conduct compressed airto the interior of said tank, the portion of the conduit within saidtank being spirally convoluted over the floor of said tank and having aplurality of perfora-' tions adapted to facilitate upward flow of air,means for controlling the flow of compressed air, means for suspendingan object in said tank and a cover for said tank having a plurality ofperforations.

3. A sandblasting machine comprising a tank adapted to contain aquantity of sand, a, conduit adapted to conduct compressed air to theinterior of said tank, the portion of the conduit within said tank beingconvoluted over the floor of said tank and having a plurality ofperforations adapted to facilitate upward flow of air, means forcontrolling the flow of compressed air through the conduit, means forsuspending an object in said tank and a cover for said tank having anair filter integral therewith,

4. A sandblasting machine comprising a tank adapted to contain aquantity of sand, a conduit adapted to conduct compressed air to theinterior of said tank, the portion of the conduit within said tank beingconvoluted over the floor of said tank and having a plurality ofperforations adapted to facilitate upward flow of air, means forcontrolling the flow of compressed air through the conduit, means forsuspending an object in said tank, a cover for said tank having a filter4 integral therewith, said filter being composed of horizontallydisposed laminations of a plurality of porous substances, and means forhermetically sealing said cover to said tank.

5. A sandblasting machine comprising a tank adapted to contain aquantity of sand, a conduit adapted to conduct compressed air to theinterior of said tank, the portion of the conduit within said tank beingspirally convoluted over the floor of said tank and having a pluralityof perforations adapted to facilitate upward flow of air, means forsuspending an object in said tank, a cover for said tank having a filterintegral therewith, said filter being composed of horizontally disposedlaminations of a plurality of porous substances, an annular inner flangeon the lower periphery of the rim of said cover, a resilient ringmounted on the crest of said flange and 11181118 for hermeticallysealing said cover to said tan ALBERT J. PORCELLI.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 7 Number Name Date 554,300 Parker Feb, 11, 18961,635,007 Orem July 5, 1927 2,007,844 Baliko July 9, 1935 2,058,218Duccini et a1. Oct. 20, 1936 2,384,414 Antrim Sept. 4, 1945

